001package ca.uhn.fhir.rest.server.interceptor;
002
003/*-
004 * #%L
005 * HAPI FHIR - Server Framework
006 * %%
007 * Copyright (C) 2014 - 2022 Smile CDR, Inc.
008 * %%
009 * Licensed under the Apache License, Version 2.0 (the "License");
010 * you may not use this file except in compliance with the License.
011 * You may obtain a copy of the License at
012 *
013 *      http://www.apache.org/licenses/LICENSE-2.0
014 *
015 * Unless required by applicable law or agreed to in writing, software
016 * distributed under the License is distributed on an "AS IS" BASIS,
017 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
018 * See the License for the specific language governing permissions and
019 * limitations under the License.
020 * #L%
021 */
022
023
024import ca.uhn.fhir.context.FhirContext;
025import ca.uhn.fhir.interceptor.api.Hook;
026import ca.uhn.fhir.interceptor.api.Interceptor;
027import ca.uhn.fhir.interceptor.api.Pointcut;
028import ca.uhn.fhir.rest.api.Constants;
029import ca.uhn.fhir.rest.api.server.RequestDetails;
030import ca.uhn.fhir.util.MetaUtil;
031import org.hl7.fhir.instance.model.api.IBaseResource;
032import org.slf4j.Logger;
033import org.slf4j.LoggerFactory;
034
035import static org.apache.commons.lang3.StringUtils.isNotBlank;
036
037/**
038 * This interceptor examines a header on the incoming request and places it in
039 * <code>Resource.meta.source</code> (R4 and above) or in an extension on <code>Resource.meta</code>
040 * with the URL <code>http://hapifhir.io/fhir/StructureDefinition/resource-meta-source</code> (DSTU3).
041 * <p>
042 * This interceptor does not support versions of FHIR below DSTU3.
043 * </p>
044 *
045 * @see <a href="http://hl7.org/fhir/resource-definitions.html#Resource.meta">Meta.source</a>
046 */
047@Interceptor
048public class CaptureResourceSourceFromHeaderInterceptor {
049
050        private static final Logger ourLog = LoggerFactory.getLogger(CaptureResourceSourceFromHeaderInterceptor.class);
051        private final FhirContext myFhirContext;
052        private String myHeaderName;
053
054        public CaptureResourceSourceFromHeaderInterceptor(FhirContext theFhirContext) {
055                myFhirContext = theFhirContext;
056                setHeaderName(Constants.HEADER_REQUEST_SOURCE);
057        }
058
059        /**
060         * Provides the header name to examine in incoming requests. Default is {@link ca.uhn.fhir.rest.api.Constants#HEADER_REQUEST_SOURCE "X-Request-Source"}.
061         */
062        @SuppressWarnings("WeakerAccess")
063        public String getHeaderName() {
064                return myHeaderName;
065        }
066
067        /**
068         * Provides the header name to examine in incoming requests. Default is {@link ca.uhn.fhir.rest.api.Constants#HEADER_REQUEST_SOURCE "X-Request-Source"}.
069         */
070        @SuppressWarnings("WeakerAccess")
071        public void setHeaderName(String theHeaderName) {
072                myHeaderName = theHeaderName;
073        }
074
075        @Hook(Pointcut.SERVER_INCOMING_REQUEST_PRE_HANDLED)
076        public void extractSource(RequestDetails theRequestDetails) {
077                IBaseResource resource = theRequestDetails.getResource();
078                if (resource != null) {
079                        String requestSource = theRequestDetails.getHeader(getHeaderName());
080                        if (isNotBlank(requestSource)) {
081                                ourLog.trace("Setting Meta.source to \"{}\" because of header \"{}\"", requestSource, getHeaderName());
082                                MetaUtil.setSource(myFhirContext, resource, requestSource);
083                        }
084                }
085        }
086}